#include<iostream>
#include<string>
#include<vector>
using namespace std;

class Solution {
public:
	void reverseString(vector<char>& s) {
		int left = 0, right = s.size() - 1;
		while (left < right) {
			char temp = s[left];
			s[left] = s[right];
			s[right] = temp;
			left++;
			right--;
		}
	}
};

void main() {
	vector<char> test = { 'H','a','n','n','a','h' };
	Solution s;
	s.reverseString(test);
	cout << test[0] << endl;
}